Information is very easy to distribute in the modem information society in electric form. Messages and computer readable files of various types can be sent individually or to predetermined or even non-defined groups of recipients using e-mail, Internet newsgroups, instant messaging, Multi-media Messaging Service (MMS) and Short Message Service (SMS). The last two of the examples are services provided by modem cellular telecommunications networks, the others are Internet enabled services and also supported by the modem mobile phones.
The ease of communications has also brought about new difficulties with access control as copyrighted, confidential, private and corporate owned data are stored and communicated to different recipients. To control data access, various mechanisms have been devised. For instance, particular infrastructure solutions have been developed, including firewalls, closed intranets, password protected encryption of documents provided by office suit applications such as Microsoft Word™ and PKZip™ and dedicated encryption applications including PGP (Pretty Good Privacy). Also World Wide Web (WWW) based home pages are provided in markup languages such as Hyper-Text Markup Language (HTML) and access controlled by passwords. The access control of data also covers controlling the manipulation of data, such as printing, copying, editing and redistributing. Digital Rights Management (DRM) and different certification systems designed by the Open Mobile Alliance™ (OMA) and Verisign™ among others, respectively, enable authentication and integrity protection of content so that one could trust that the data originates from given source and is somewhat reliable (Verisign™) and so that rights of the owner of the data are respected. Some applications such as Adobe Acrobat Reader™ protect content against editing, copying and printing for documents when used to view the content. OMA DRM takes an extra step and also should prevent unauthorized distribution of content to protect businesses such as ring tone sales against free copying.
It is noteworthy, however, that any content protection that yet allows a user to actually see and/or hear protected content is yet quite exposed to simple copying with a suitable media recorder or by tapping to the wires of user's own data output device such as loudspeakers. The quality may slightly degrade, but this risk still exists. Moreover, the application specific data access control measures such as passwords imposed by office applications are typically easy to break with commonly available software. The encryption or other access protection also typically involves prompting and reading a password or smart card from the user, which may be perceived as too laborious for normal documents such as personal e-mails. Legitimate use is also complicated and even frustration may be caused when content protection hinders taking normal back-up copies, for instance. As result, probably most of present non-public electric content is yet unprotected and uncontrolled and thus can easily spread in an undesired manner even without any bad intention.